tonic
UK: ˈtɒnɪk | US: ˈtɑːnɪk
n. 1. A medicinal substance to invigorate or restore health.
n. 2. Something that strengthens or refreshes.
n. 3. (Music) The first note of a diatonic scale; keynote.
adj. Relating to or producing tone, especially in muscles.
The word "tonic" traces back to the Greek tonos (tension, pitch), which evolved into Latin tonus (sound, tone). The suffix -ic (from Greek -ikos) denotes "relating to." Originally used in music (referring to the "keynote"), it later expanded to medicine (a "strengthening agent") due to the idea of restoring bodily "tone" or vigor. The dual meanings reflect both auditory and physiological concepts of tension and balance.
She drank a herbal tonic to boost her energy.
The cheerful music acted as a tonic for his mood.
In C major, the tonic note is C.
The doctor prescribed a muscle tonic for recovery.
His speech was a tonic for the discouraged team.